Refactor duplicated error handling and validation utilities

[Copilot]

Extracted repeated error handling, file operations, and validation patterns into shared utilities across CLI and SDK packages.

Changes

CLI File Operations (packages/ums-cli/src/utils/file-operations.ts)

• Extracted getErrorMessage() to eliminate 4 instances of error instanceof Error ? error.message : String(error)
• Consolidated file reading via readFileWithContext() helper

SDK File Utils (packages/ums-sdk/src/utils/file-utils.ts)

• Added isFileNotFoundError() type guard with proper string validation for error.code
• Replaced inline ENOENT checking in 2 locations

SDK Loader Utils (packages/ums-sdk/src/loaders/loader-utils.ts) - new file

• filePathToUrl() - consolidates pathToFileURL().href pattern from both loaders
• formatValidationErrors() - eliminates duplicated validation error formatting

Module/Persona Loaders

• Updated to use shared utilities from loader-utils

Before

// Repeated in module-loader.ts and persona-loader.ts
const fileUrl = pathToFileURL(filePath).href;

const errorMessages = validation.errors
  .map(e => `${e.path ?? 'module'}: ${e.message}`)
  .join('; ');

After

import { filePathToUrl, formatValidationErrors } from './loader-utils.js';

const fileUrl = filePathToUrl(filePath);
const errorMessages = formatValidationErrors(validation, 'module');

Test Coverage

• Added 8 tests for loader-utils
• Added 6 tests for file-utils enhancements
• All existing 486 tests pass

Original prompt

Find and refactor duplicated code

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[Copilot]

Pull request overview

This PR refactors duplicated error handling and validation utilities across CLI and SDK packages, extracting common patterns into shared utility functions to improve code maintainability and reduce duplication.

Key changes:

• Extracted error message formatting helper in CLI file operations
• Added type-safe file error checking utilities in SDK
• Created new loader-utils module with validation error formatting and file URL conversion helpers

Reviewed changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/ums-sdk/src/utils/file-utils.ts	Added isFileNotFoundError() type guard with proper validation, replacing inline ENOENT checks
packages/ums-sdk/src/utils/file-utils.test.ts	Added 6 comprehensive tests for new isFileNotFoundError() function
packages/ums-sdk/src/loaders/loader-utils.ts	New utility module with filePathToUrl() and formatValidationErrors() helpers
packages/ums-sdk/src/loaders/loader-utils.test.ts	Added 8 tests covering both new utility functions
packages/ums-sdk/src/loaders/persona-loader.ts	Updated to use shared utilities from loader-utils, removing duplicated code
packages/ums-sdk/src/loaders/module-loader.ts	Updated to use shared utilities from loader-utils and file-utils
packages/ums-cli/src/utils/file-operations.ts	Extracted getErrorMessage() and readFileWithContext() helpers to eliminate duplication
package-lock.json	Dependency management changes including tsx and peer dependency markers

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[Copilot]

This error message construction still uses the inline pattern that was supposed to be refactored. Consider extracting this to a helper function like getErrorMessage() in the CLI package to maintain consistency with the stated goal of eliminating duplicated error handling patterns. The same pattern exists in several other SDK files (high-level-api.ts lines 142 and 196, module-discovery.ts line 91, standard-library.ts line 60, build-orchestrator.ts line 163).